Way Huge Pickle MK2 has two of these diode pots. One between LED and silicon, the other silicon and bypass.
This diode pot is a common feature on VFE pedals too with the center position sounding like the diodes are bypassed. There's the Alpha Dog (Rat) on the main page, and the Fiery Red Big Muff, which you can find at Madbean. There's also the Distortion 3, which was one of my first layouts here:
http://guitar-fx-layouts.42897.x6.nabble.com/VFE-Distortion-3-quot-cubed-quot-layout-td36720.htmlMost of the time, I was good with a B100k pot, but some diode combos required more experimentation to avoid dead spots and make the transition smooth. The VFE pots use a center detent, but you'll hear when the diodes sound bypassed.
As far as the germanium pair, double up to raise the level.